diff options
Diffstat (limited to 'mm/hmm.c')
| -rw-r--r-- | mm/hmm.c | 62 |
1 files changed, 32 insertions, 30 deletions
@@ -153,9 +153,8 @@ static void hmm_release(struct mmu_notifier *mn, struct mm_struct *mm) /* Wake-up everyone waiting on any range. */ mutex_lock(&hmm->lock); - list_for_each_entry(range, &hmm->ranges, list) { + list_for_each_entry(range, &hmm->ranges, list) range->valid = false; - } wake_up_all(&hmm->wq); mutex_unlock(&hmm->lock); @@ -166,9 +165,10 @@ static void hmm_release(struct mmu_notifier *mn, struct mm_struct *mm) list_del_init(&mirror->list); if (mirror->ops->release) { /* - * Drop mirrors_sem so callback can wait on any pending - * work that might itself trigger mmu_notifier callback - * and thus would deadlock with us. + * Drop mirrors_sem so the release callback can wait + * on any pending work that might itself trigger a + * mmu_notifier callback and thus would deadlock with + * us. */ up_write(&hmm->mirrors_sem); mirror->ops->release(mirror); @@ -223,11 +223,8 @@ static int hmm_invalidate_range_start(struct mmu_notifier *mn, int ret; ret = mirror->ops->sync_cpu_device_pagetables(mirror, &update); - if (!update.blockable && ret == -EAGAIN) { - up_read(&hmm->mirrors_sem); - ret = -EAGAIN; - goto out; - } + if (!update.blockable && ret == -EAGAIN) + break; } up_read(&hmm->mirrors_sem); @@ -271,6 +268,7 @@ static const struct mmu_notifier_ops hmm_mmu_notifier_ops = { * * @mirror: new mirror struct to register * @mm: mm to register against + * Return: 0 on success, -ENOMEM if no memory, -EINVAL if invalid arguments * * To start mirroring a process address space, the device driver must register * an HMM mirror struct. @@ -298,7 +296,7 @@ EXPORT_SYMBOL(hmm_mirror_register); /* * hmm_mirror_unregister() - unregister a mirror * - * @mirror: new mirror struct to register + * @mirror: mirror struct to unregister * * Stop mirroring a process address space, and cleanup. */ @@ -372,7 +370,7 @@ static int hmm_pfns_bad(unsigned long addr, * @fault: should we fault or not ? * @write_fault: write fault ? * @walk: mm_walk structure - * Returns: 0 on success, -EBUSY after page fault, or page fault error + * Return: 0 on success, -EBUSY after page fault, or page fault error * * This function will be called whenever pmd_none() or pte_none() returns true, * or whenever there is no page directory covering the virtual address range. @@ -911,6 +909,7 @@ int hmm_range_register(struct hmm_range *range, unsigned page_shift) { unsigned long mask = ((1UL << page_shift) - 1UL); + struct hmm *hmm; range->valid = false; range->hmm = NULL; @@ -924,28 +923,29 @@ int hmm_range_register(struct hmm_range *range, range->start = start; range->end = end; - range->hmm = hmm_get_or_create(mm); - if (!range->hmm) + hmm = hmm_get_or_create(mm); + if (!hmm) return -EFAULT; /* Check if hmm_mm_destroy() was call. */ - if (range->hmm->mm == NULL || range->hmm->dead) { - hmm_put(range->hmm); + if (hmm->mm == NULL || hmm->dead) { + hmm_put(hmm); return -EFAULT; } - /* Initialize range to track CPU page table update */ - mutex_lock(&range->hmm->lock); + /* Initialize range to track CPU page table updates. */ + mutex_lock(&hmm->lock); - list_add_rcu(&range->list, &range->hmm->ranges); + range->hmm = hmm; + list_add_rcu(&range->list, &hmm->ranges); /* * If there are any concurrent notifiers we have to wait for them for * the range to be valid (see hmm_range_wait_until_valid()). */ - if (!range->hmm->notifiers) + if (!hmm->notifiers) range->valid = true; - mutex_unlock(&range->hmm->lock); + mutex_unlock(&hmm->lock); return 0; } @@ -960,17 +960,19 @@ EXPORT_SYMBOL(hmm_range_register); */ void hmm_range_unregister(struct hmm_range *range) { + struct hmm *hmm = range->hmm; + /* Sanity check this really should not happen. */ - if (range->hmm == NULL || range->end <= range->start) + if (hmm == NULL || range->end <= range->start) return; - mutex_lock(&range->hmm->lock); + mutex_lock(&hmm->lock); list_del_rcu(&range->list); - mutex_unlock(&range->hmm->lock); + mutex_unlock(&hmm->lock); /* Drop reference taken by hmm_range_register() */ range->valid = false; - hmm_put(range->hmm); + hmm_put(hmm); range->hmm = NULL; } EXPORT_SYMBOL(hmm_range_unregister); @@ -978,7 +980,7 @@ EXPORT_SYMBOL(hmm_range_unregister); /* * hmm_range_snapshot() - snapshot CPU page table for a range * @range: range - * Returns: -EINVAL if invalid argument, -ENOMEM out of memory, -EPERM invalid + * Return: -EINVAL if invalid argument, -ENOMEM out of memory, -EPERM invalid * permission (for instance asking for write and range is read only), * -EAGAIN if you need to retry, -EFAULT invalid (ie either no valid * vma or it is illegal to access that range), number of valid pages @@ -1061,7 +1063,7 @@ EXPORT_SYMBOL(hmm_range_snapshot); * hmm_range_fault() - try to fault some address in a virtual address range * @range: range being faulted * @block: allow blocking on fault (if true it sleeps and do not drop mmap_sem) - * Returns: number of valid pages in range->pfns[] (from range start + * Return: number of valid pages in range->pfns[] (from range start * address). This may be zero. If the return value is negative, * then one of the following values may be returned: * @@ -1179,7 +1181,7 @@ EXPORT_SYMBOL(hmm_range_fault); * @device: device against to dma map page to * @daddrs: dma address of mapped pages * @block: allow blocking on fault (if true it sleeps and do not drop mmap_sem) - * Returns: number of pages mapped on success, -EAGAIN if mmap_sem have been + * Return: number of pages mapped on success, -EAGAIN if mmap_sem have been * drop and you need to try again, some other error value otherwise * * Note same usage pattern as hmm_range_fault(). @@ -1267,7 +1269,7 @@ EXPORT_SYMBOL(hmm_range_dma_map); * @device: device against which dma map was done * @daddrs: dma address of mapped pages * @dirty: dirty page if it had the write flag set - * Returns: number of page unmapped on success, -EINVAL otherwise + * Return: number of page unmapped on success, -EINVAL otherwise * * Note that caller MUST abide by mmu notifier or use HMM mirror and abide * to the sync_cpu_device_pagetables() callback so that it is safe here to @@ -1390,7 +1392,7 @@ static void hmm_devmem_free(struct page *page, void *data) * @ops: memory event device driver callback (see struct hmm_devmem_ops) * @device: device struct to bind the resource too * @size: size in bytes of the device memory to add - * Returns: pointer to new hmm_devmem struct ERR_PTR otherwise + * Return: pointer to new hmm_devmem struct ERR_PTR otherwise * * This function first finds an empty range of physical address big enough to * contain the new resource, and then hotplugs it as ZONE_DEVICE memory, which |